// Copyright (c) 2012 The Chromium Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.

#include "base/command_line.h"
#include "base/metrics/histogram_macros.h"
#include "media/base/media_switches.h"

#if defined(USE_ALSA)
#include "media/audio/alsa/audio_manager_alsa.h"
#else
#include "media/audio/fake_audio_manager.h"
#endif
#if defined(USE_CRAS)
#include "media/audio/cras/audio_manager_cras.h"
#endif
#if defined(USE_PULSEAUDIO)
#include "media/audio/pulse/audio_manager_pulse.h"
#endif

namespace media {

enum LinuxAudioIO {
    kPulse,
    kAlsa,
    kCras,
    kAudioIOMax = kCras // Must always be equal to largest logged entry.
};

ScopedAudioManagerPtr CreateAudioManager(
    scoped_refptr<base::SingleThreadTaskRunner> task_runner,
    scoped_refptr<base::SingleThreadTaskRunner> worker_task_runner,
    AudioLogFactory* audio_log_factory)
{
#if defined(USE_CRAS)
    if (base::CommandLine::ForCurrentProcess()->HasSwitch(switches::kUseCras)) {
        UMA_HISTOGRAM_ENUMERATION("Media.LinuxAudioIO", kCras, kAudioIOMax + 1);
        return ScopedAudioManagerPtr(
            new AudioManagerCras(std::move(task_runner),
                std::move(worker_task_runner), audio_log_factory));
    }
#endif

#if defined(USE_PULSEAUDIO)
    // Do not move task runners when creating AudioManagerPulse.
    // If the creation fails, we need to use the task runners to create other
    // AudioManager implementations.
    std::unique_ptr<AudioManagerPulse, AudioManagerDeleter> manager(
        new AudioManagerPulse(task_runner, worker_task_runner,
            audio_log_factory));
    if (manager->Init()) {
        UMA_HISTOGRAM_ENUMERATION("Media.LinuxAudioIO", kPulse, kAudioIOMax + 1);
        return std::move(manager);
    }
    DVLOG(1) << "PulseAudio is not available on the OS";
#endif

#if defined(USE_ALSA)
    UMA_HISTOGRAM_ENUMERATION("Media.LinuxAudioIO", kAlsa, kAudioIOMax + 1);
    return ScopedAudioManagerPtr(
        new AudioManagerAlsa(std::move(task_runner),
            std::move(worker_task_runner), audio_log_factory));
#else
    return ScopedAudioManagerPtr(
        new FakeAudioManager(std::move(task_runner),
            std::move(worker_task_runner), audio_log_factory));
#endif
}

} // namespace media
